Internal pipe gripping tool



Nov. 6, 1956 L. R. HOLMES INTERNAL. PIPE GRIPPING TOOL Filed April lO, 1953 United States Patent() 2,769,655 INTERNAL PIPE GRIPPING Toor Lloyd R. Holmes, Vermillion, S. Dak. Application April 10, 1953, Serial No. 348,029 Claims. (Cl. 294-494) My invention is a tool for use with drilling rigs in gripping pipes internally and it employs a novel means for holding the gripping portion of the tool against rotation 'for tightening until such time as the tool begins to grip.

In many well drilling operations pipes are inserted in the `ground to prevent the drilled hole from being plugged bydirt after it has been drilled. When the well is abandoned it is frequently advisable to pull the pipe out of the ground in order to make it available for reuse. The methods and tools now used for pulling pipes are not enti-rely satisfactory. Those known to me grip the pipe a't the top. Much of the pipe is lost when present equipment is used. When the pipe breaks down in the ground, conventional equipment will not retrieve the pipe. In very deep wells the earth exerts a very great force on the pipe and the possibilities of pulling the pipe successfully are greatly reduced.

In view of all of the shortcomings of the prior art it is the principal object of my invention to provide an internal pipe gripping tool that grips the interior of a pipe.

It is a further object of my invention to provide an internal pipe gripping tool that can be tightened at a point far removed from and intermediate the ends of the pipe.

It is a further object of my invention to provide an internal pipe gripping tool that is easily removed from the pipe after the pipe has been pulled.

It is a further object of my invention to provide an internal pipe gripping tool that is economical to manufacture and durable in use.

These and other objects will be apparent to those skilled in the art.

My invention consists in the construction, arrangement and combination of the various parts of the device, whereby the objects contemplated are attained as hereinafter more fully set forth, and specifically pointed out in my claims, and illustrated in the accompanying drawings, in which:

Fig. l is a perspective view of my tool and a fragment of a pipe,

Fig. 2 is a greatly enlarged vertical sectional view of my tool engaging the interior of a pipe imbedded in the ground taken on the line 2-2 of Fig. l, and

Fig. 3 is a cross sectional View of my new pipe pulling tool taken on the line 3-3 of Fig. l.

Referring to the drawings, the numeral 10 designates the shaft of a well drilling rig or the end of a drill rod provided with some means for gripping the various tools that are used with the drilling rig. As shown here the element 10 is threaded internally to permit drilling tools and the like to be secured to it. These threads of element 10 are not shown but may be reasonably deduced from the threads 12 formed on the top of the tapered tool core 14. Core 14 is provided with two other sets of threads; the tapered threads 16 and the straight threads 18. The tapered threads 16 engage the female tapered threads 20 of the expanding spring steel cylindrical element or split sleeve 22. The sleeve may be provided with any number of slots and I have shown three which are all 2,769,655 Patented Nov;` 6, 6

ICC

designated 24. The slots stop near the bottom of the sleeve as can be seen vin Fig. t2. At this point the sleeve narrows to provide a bearing 26 that slidably and rotatably receives the end 28 of the tapered core 14. A series of stiff wire bristles form a yielding friction creating means :29 and are secured to the outside of the bearing portion 26. These bristles extend beyond the .perimeter of ysleeve 22 and engage the inside of a well casing pipe or the like such as the one designated 30 in Fig. 2.. t The threads 18 receive a nut 32 which is appropriately safetied as with the `cotter key 34. The outside of the sleeveis knurled or serrated to provide a gripping surface on the sleeve that will engage the inside of the pipe with little or no chance of slipping. A passageway designated. 36 is formed in the tapered core to permit back-flushing if such anoperation should prove necessary or desirable.` While I have described a split sleeve having three slots., it is not my intention to be limited to such a structure in my claims. Obviously the sleeve could be made in several sections and -secured together in the manner of chucks and the like. The main feature of my device `is the combination of the wire bristles with the expanding split sleeve. By using this structure it is possible to place my tool far down inside a pipe and clip it after the tool is 'insertedin the pipe, the tapered core is turned slowly. The wire bristles resist turning of the sleeve as the core is turned. As the core extends farther into the sleeve,`therefor, it fis spread which causes it to grip the pipe as shown in Fig. 2. An upward pull on the core will then lift the pipe 30 to pull it out of the ground designated 38. Olnce the pipe has been pulled it is easily disconnected from the tool by simply turning core 14 in the opposite direction to that used for tightening it and the spring steel sleeve 22 will self-contract. lt should be clear, therefore, that I have provided a pipe gripping tool that will accomplish the objects of my invention. A

Some changes may be made in the construction and arrangement of my internal pipe gripping tool without departing from the real spirit and purpose of my invention, and it is my intention to cover by my claims, any modified forms of structure or use of mechanical equivalents which may be reasonably included within their scope.

lclaim:

l. l'n combination, a pipe buried in the ground and a tool for engaging and gripping the interior surface of said pipe at a point remote from and intermediate of its ends; said tool comprising, a hollow internally tapered and threaded partially split sleeve, a tapered threaded core threadably engaging said hollow internally tapered and threaded partially split sleeve for expanding the same into gripping engagement with the interior surface of the pipe, a plurality of stiff bristles secured to said sleeve and extending beyond its periphery, means secured to said core to limit movement of said core relative to said sleeve in one direction, and means secured to the top of said core for securing it to a well drilling rig; said bristles describing a circle larger than the internal diameter of said pipe and frictionally engageable therewith to limit rotation of the sleeve relative to said pipe.

2. In combination, a pipe buried in the ground and a tool for engaging and gripping the interior of said pipe at a point intermediate its ends; said tool comprising; a hollow spring metal sleeve being partially split and internally tapered and threaded; a core being externally tapered and threaded, and threadably engaging said sleeve for expanding the same; said spring metal sleeve selfcontracting when permitted to do so by said core, means secured to said core to prevent disengagement of said core from said sleeve by upward movement of said core, yielding friction creating means carried by said sleeve and extending beyond the circumference thereof and being greater in lateral measurement than the interior of said pipe for frietional engagement therewith to limit rotation of the sleeve relative to said pipe, and means secured to the top of said core for operatively securing the tool to a well drilling rig.

' 3. In a pipe gripping-tool for engaging andgripping the interior surface of a pipe at a point removed from and intermediate its ends; a hollow spring metal sleeve being partially split andinternally tapered and threaded; a core, externally tapered and threaded and threadable, engaging said sleeve for expanding the same; saidV spring metal sleeve self-contracting when permitted to do so by said core; means secured to said core to prevent disengagement of said core from said-sleeve relative longitudinal movement ofv saidcore and-sleeve; yielding friction creating means carried by said sleeve for frictionally engaging the interior surface of the pipe to 'limit rotation of the sleeve relative to said pipe;and means secured to the top of said core for operatively securing the tool to a well drilling rig.

4. The 'combination set forth in claim 3 wherein the yielding friction creating means comprises a plurality of stit bristles carried bythe sleeve and extending radially beyond the circumference of said sleeve.

5. In a pipe gripping tool for engaging and gripping the interior surface of a pipe at a point removed from and intermediate its ends; a cylindrical expanding unit having an internal tapered and threaded portion; a core, externally tapered and threaded and threadably engaging said unit for expanding the same; means secured to said core to prevent disengagement of said core from said unit upon relative longitudinal movement of said core and unit; yielding friction creating means carried by said unit 4 for frictionally engaging the interior surface of the pipe to limit rotation of the unit relative to said pipe; and means secured to the top of said core for operatively securing the tool to a well drilling rig.

6. The combination set forth in claim 2 wherein the hollow sleeve comprises a cylindrical expanding unit having an internal tapered and threaded portion.

7. The combination of claim 2 further characterized by having a passageway extending through said core.

8. The combination of claim 7 further characterized by having said sleeve externally knurled.

9. The pipe gripping tool of claim 3 further characterized by a passageway formed in said core.

10. The pipe gripping tool of claim 3 further characterized by said sleeve being externally knurled.

References Cited in the le of this patent UNITED STATES PATENTS 232,406 Lamb Sept. 21, 1880 881,353 Stewart Mar. 10, 1908 881,496 Seamen Mar. 10, '1908 942,515 Poole Dec. 7, 1909 1,441,583 Humason et al. Jan. 9, 1923 1,671,429 Janney May 29, 1928 2,184,681 Osmun et al Dec. 26, 1939 2,355,854 Gean et al Aug. 15, 1944 2,495,793 Webb Jan. 31, 1950 2,604,170 Leiller July 22, 1952 2,654,433 Piety Oct. 6, 1953 

